package com.analog.mserver.shiro;

import org.apache.shiro.authc.AuthenticationException;
import org.apache.shiro.authc.AuthenticationInfo;
import org.apache.shiro.authc.AuthenticationToken;
import org.apache.shiro.authc.SimpleAuthenticationInfo;
import org.apache.shiro.authz.AuthorizationInfo;
import org.apache.shiro.authz.SimpleAuthorizationInfo;
import org.apache.shiro.realm.AuthorizingRealm;
import org.apache.shiro.subject.PrincipalCollection;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

import com.analog.mserver.domain.user.UserEntity;
import com.analog.mserver.jwt.JwtToken;
import com.analog.mserver.jwt.JwtUtil;
import com.analog.mserver.service.user.UserService;

@Component
public class MyRealm extends AuthorizingRealm {

	@Autowired
	private UserService userService;

	/**
	 * 必须重写此方法，不然Shiro会报错
	 */
	@Override
	public boolean supports(AuthenticationToken token) {
		return token instanceof JwtToken;
	}

	/**
	 * 只有当需要检测用户权限的时候才会调用此方法，例如checkRole,checkPermission之类的
	 */
	@Override
	protected AuthorizationInfo doGetAuthorizationInfo(PrincipalCollection principals) {
		String username = JwtUtil.getUsername(principals.toString());
		UserEntity userBean = userService.findByUsername(username);
		SimpleAuthorizationInfo simpleAuthorizationInfo = new SimpleAuthorizationInfo();
		return simpleAuthorizationInfo;
	}

	/**
	 * 默认使用此方法进行用户名正确与否验证，错误抛出异常即可。
	 */
	@Override
	protected AuthenticationInfo doGetAuthenticationInfo(AuthenticationToken auth) throws AuthenticationException {
		String token = (String) auth.getCredentials();
		// 解密获得username，用于和数据库进行对比
		String username = JwtUtil.getUsername(token);
		if (username == null) {
			throw new AuthenticationException("token is null");
		}

		UserEntity userBean = userService.findByUsername(username);
		if (userBean == null) {
			throw new AuthenticationException("用户不存在!");
		}

		if (!JwtUtil.verify(token, username, userBean.getPassword())) {
			throw new AuthenticationException("用户名或密码错误");
		}

		return new SimpleAuthenticationInfo(token, token, "my_realm");
	}
}